The demand for German-built robot pigs is growing, according to a UPI news story. The autonomous robot pigs are part of a cost-effective, evironmentally friendly, solar drying process for sewage plants. Sewage is spread over a large area where it absorbs the sun's heat, causing evaporation of water, which lowers the mass of the sewage. The robot pigs assist by constanly churning the sewage. The robot pigs, produced by Thermo-System GmbH, are also known as electric pigs, and electric moles. The pigs look a bit like Volkswagon Beetles. For more details, see the robot pig's specifications (PDF format).